Since Big Finish acquired the rights to the new series of Doctor Who, there have been countless audio adventures featuring characters from the sci-fi series' 2005 reboot. The audio company has explored everything from the adventures of River Song to an anthology series set on New Earth.

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One of the most popular new series is Classic Doctors, New Monsters. Big Finish has released two of these fan-favorite box sets to date, which pairs classic series Doctors such as Tom Baker and Paul McGann with some of the new series' most monstrous creations. These stories are among some of Big Finish's finest releases, offering listeners a chance to witness what happens when these two distinct eras collide.

The Sontaran Ordeal

The Eighth Doctor, Sarana Teel and a Sontaran on the cover for The Sontaran Ordeal

Released as a part of the first box set, "The Sontaran Ordeal" is set during the Time War and sees Paul McGann's Doctor come face to face the new series' version of the Sontarans. Upon arriving on the planet Drakkis, the Doctor is reluctantly forced to team up with the Sontaran Commander Jask, in order to save the planet from becoming the Time War's latest casualty.

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"The Sontaran Ordeal" is an effective character piece, as it offers some fascinating observations regarding the similarities between the Sontarans and the Time Lords. Sontaran actor Christopher Ryan delivers an excellent performance, which helps to justify the Sonatarans' inclusion as a new series monster, despite having originated in the classic series.

Night Of The Vashta Nerada

Tom Baker on the cover of Night Of The Vashta Nerada, with a Vashta Nerada from Silence In The Library/Forest Of The Dead next to him.

Often considered the most likable Doctor, Tom Baker's incarnation of the legendary Time Lord features in Classic Doctors New Monsters' second box set. In the opening story, entitled "Night of the Vashta Nerada," the Doctor encounters a swarm of Vashta Nerada in the intergalactic theme park Funworld.

The audio drama delivers an action-packed 45 minutes, as the Doctor and his new friends are hunted by the flesh-eating monsters across the amusement resort. Tom Baker is electrifying throughout, providing a more dramatic portrayal of his incarnation which suits the story's darker tone.

Day of the Vashta Nerada

Paul McGann and Jaqueline Pearce on the cover of Day Of The Vashta Nerada, with a Vashta Nerada from Silence In The Library/Forest Of The Dead next to him.

In a first for the Classic Doctors New Monsters range, the Vashta Nerada - who many fans want to see return in Series 13 - appear twice in the second volume. This time, the shadow creatures are heard terrorizing Paul McGann's Doctor in the box set's closing adventure "Day of the Vashta Nerada."

The audio's narrative concerns the Time Lords' attempts to weaponize the Vashta Nerada, in order to increase their firepower in the midst of the Time War. It provides a unique angle on the carnivorous monsters, which leads to many creepy moments as the creatures inevitably break free. The introduction of the 'Nerada Vashta,' who prey on humanoid flesh in brightly lit spaces, adds some greater stakes to the drama, whilst Jaqueline Pearce as Ollistra provides plenty of entertaining moments throughout.

Harvest Of The Sycorax

The Seventh Doctor and a Sycorax on the cover of Harvest Of The Sycorax

Sylvester McCoy's only Classic Doctors New Monsters story stars the Sycorax, a race that appeared in one of Doctor Who's greatest Christmas Specials.  "Harvest Of The Sycorax" can be found in the audio range's first box set and sees the Doctor arrive on a space station where the human race has been sold as slaves to the Sycorax.

The story perfectly evokes the feel of Sylvester McCoy's first season as the Doctor, with McCoy emulating his goofier portrayal from his initial run of episodes. Writer James Goss also imbues the script with some truly thought-provoking themes, concerning the idea of emotions being treated as diseases long into the future. "Harvest Of The Sycorax" proves to be a truly excellent second outing for the Sycorax species.

The Carrionite Curse

The Sixth Doctor and a Carrionite on the cover of The Carrionite Curse

First seen in the episode "The Shakespeare Code", the Carrionites are a particularly memorable creation from Doctor Who's third series. Their Classic Doctors New Monsters debut features the witches coming to blows with Colin Baker's Doctor, during a buskers' fair in the 1980s.

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"The Carrionite Curse" is an audio adventure that fits Colin Baker's Doctor perfectly, as the witches' powerful wordplay makes for the ideal foil for the Sixth Doctor's linguistic techniques. The narrative also contains the rather novel backdrop of a witch trial occurring in the 1980s, which helps to make this a Doctor Who tale to remember.

Fallen Angels

The Fifth Doctor and Matthew Kelly's Michelangelo with a Weeping Angel on the cover of Fallen Angels

Debuting in one of Doctor Who's scariest episodes, the Weeping Angels are arguably the new series' most iconic monsters. Classic Doctors New Monsters' first story also serves as the Angels' audio debut, with a chilling adventure entitled "Fallen Angels." This time it's the Fifth Doctor, played by Peter Davison, who crosses paths with the imposing stone statues.

Writer Phil Mulryne delivers an expertly crafted "timey wimey" narrative, as the Doctor meets his new friends Joel and Gabby Finch in the wrong order. The Weeping Angels' terrifying presence is felt throughout the plot, with some spine-chilling sound design used to signify their appearances in the absence of visual cues. Meanwhile, former Stars In Their Eyes host Matthew Kelly delivers a stunning portrayal of the famous painter Michelangelo, in a performance that showcases his excellent acting capabilities.

Empire Of The Racnoss

The Fifth Doctor and a Racnoss on the cover of Empire Of The Racnoss

Despite having only appeared once in the TV Series, the Racnoss are fondly remembered by Doctor Who fans across the globe.  Their first Big Finish audio, therefore, is one that proved very popular with listeners upon its release. "Empire Of The Racnoss" sees Peter Davison's Doctor flung off course by a distress signal whilst traveling through the time vortex, where he finds himself in the midst of a conflict between the Racnoss and Ancient Gallifrey.

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Expanding on a line from the episode "The Runaway Bride," "Empire Of The Racnoss" builds significantly on the mythology of the extra-terrestrial arachnids in a way that is fun and engaging. It's a layered and complex story, as the Doctor reluctantly joins forces with the Racnoss Empress - played outstandingly by Adjoa Andoh - and accidentally becomes embroiled in a Racnoss Civil War.

Judoon In Chains

The Sixth Doctor and a Judoon on the cover of Judoon In Chains

Writer Russell T Davies is responsible for many of the new series' greatest alien inhabitants, but one of his most memorable monsters is undoubtedly the Judoon. These creatures have returned a few times in the television series, but their best story comes in the form of Classic Doctors New Monsters' second audio CD, "Judoon In Chains."

This dramatically compelling narrative involves the Sixth Doctor defending Judoon Captain Kybo in a Victorian court of law, after abandoning his post in the Judoon police force upon learning about their plans to terraform Earth. It's a beautiful and profound tale, as Kybo reveals his love for poetry and recalls his harsh treatment by the human population, who view him as a 'freak' due to his rhinoceros appearance. Nicholas Briggs' voice work brings a strong sense of emotion to Kybo, allowing audiences to sympathize with the space rhino.

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