William Riker

In a parallel universe, Commander William Thomas Riker was the first officer of the Starfleet vessel USS Enterprise-D during the 24th century. As such, Capt. Picard often referred to him as "Number One."

Locutus
During the Borg invasion of the United Federation of Planets, Riker took command of the Enterprise after Picard was kidnapped by the Borg and taken aboard their cube. As Riker and the crew discovered, Picard had been assimilated into the Borg Collective as his identity was suppressed by Locutus, the emissary of the Borg. After the Borg used Picard's knowledge to easily defeat a Starfleet task force in battle of Wolf 359, Riker devised a plan to turn the tables against the Borg as they proceeded to Earth, entailing the retrieval of the Captain from the Borg cube by Lieutenants Data and Worf. Back aboard the Enterprise, Picard was freed from the Collective as he assisted Data in incapacitating the Borg cube, leading to its self-destruction. (COMIC: Assimilation²)

The Doctor and the Cybermen
In 2368, Picard sent him on a mission to check up on mining operations on Naia VII. He took Data and Worf with him and found that the mines, which were below the water level of the largely aquatic planet, had been built with insufficient regard to safety. In fact, a section of the mines flooded while he and his team were visiting. Riker was saved from drowning by Lt Cmdr Data.

After Riker returned to the Enterprise, Capt. Picard suggested that he inspect the ship's holodeck, which had just received a systems upgrade. Accompanied by Data and Beverly Crusher, he began a Dixon Hill programme set in 1940s San Francisco. He heard the Doctor's TARDIS materialise, but thought it was a bug in the upgrade. Similarly, when the Eleventh Doctor, Amy Pond and Rory Williams arrived and the Doctor identified Data as an android, Riker assumed that the simulation was malfunctioning, recognising Data as an anachronistic element in the setting. He ended the programme and was surprised to see that the Doctor, Amy, Rory and the TARDIS were not part of the simulation. After Worf escorted the trio to the ship's observation lounge, Riker asked Deanna Troi if she could sense anything from their visitors. The introductions were interrupted by news of the attack on Delta IV. (COMIC: Assimilation²)