Eric Scott 
Time Trek 2 [PDF ebook] 
Return of the Mutant

‘It was a rare malfunction in the Cryolab that led to the return of the deranged mutant Darkon. A blink in the electricity system turned the humidity meter off. It took no longer than a minute for the maintenance engineers to spot the malfunction and fix it, but the time was enough for a bead of moisture to form and drop into the softly humming motor that controlled the temperature of the open-lidded deep freeze capsule that housed the gross shape of Darkon.